<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>welcome</title>
    <style>
        div{
            width:200px;
            height:200px;
            border-style: solid;
            border-width: 1px 1px 100px;
            box-sizing: border-box;
            border-radius: 50%;
            margin: 0 auto;
            position: relative;

        }
        div::before{
            content: "";
            height: 100px;
            width: 100px;
            position: absolute;
            left: 0;
            top: 50%;
            background: white;
            border-style: solid;
            border-radius: 50%;
            border-width: 40px;
            border-color: black;
            box-sizing: border-box;

        }
        div::after{
            content: "";
            height: 100px;
            width: 100px;
            position: absolute;
            right: 0;
            top: 50%;
            border-style: solid;
            border-color: white;
            background: black;
            border-width: 40px;
            border-radius: 50%;
            box-sizing: border-box;
        }
    </style>
</head>
<body>
    <div></div>
</body>
</html>